Improvement in treating straw to obtain paper-pulp



UNITE STATES PATENT 1 OFFICE.

THEODORE A; sixes, or PHILADELPHIA,

IM PROVEM ENT m TR EATING'STRAW "To c imi PA pg l u -p,

Specification forming part of Letters Patent'No. 47,2 l7, d ated April '1 1,.1865.

1'0 all whom, it may concern.- 7 Be it known that I, THEODORE A; NIXON of Philadelphia, Pennsylvania,have invented an Improved Mode of Treating Straw to Obtain Paper-Pulp; and I do hereby declare the following to be a full, clear, and exact description of the same' My invention consists, first, inmanufactur-- ing paper-pulp from-straw by a process substantially asdescribed hereinafter, whereby the pulp is improved in quality and the 6X",

peuse ot' the operation greatly lessened; secondly. in subjecting the prepared strawto the action of a hot solution of alkali previous to boiling the same, substantially as described hereinafter, the time required for the opera tion being thus greatly shortened and the full strength of the alkali for dissolving the gluten, silica, &c., being obtained.

In order to enable others skilled in the art to make and use my invention, I will now pro-' reed to describe its construction. and operat-ion. r

I nto a tub of suitable size is placed a given amount of raw straw, and upon the latter is poured such a quantity of alkaline liquor (prepared as described hereinafter) as may be neecssziry to cover the whole. The liquor is then limited by means of a coil of steam-pipe in the tub, and is kept at the boiling-point for about six hours, by which time the straw will become soft and pliable. The tub is now filled with water, and a cock at the bottom of the same is opened, so that the liquor may escape, fresh warm water being constantly admitted at the top o f the tub, which is thus'inaintained full, this operation being continubd until the straw is thoroughly washed and all loosened portions of gluten, silica, and foreign matter are removed. The warm straw is then thrown intoa boiler, and-a solution of caustic soda of about3-.- alkalimeter and heated to 250 Fahrenheit is then poured over the same. After this the boiler is closed, and steam is introduced and Vmaintained at about sixty pounds pressure until allthe remaining gluten and silica are dissolved and the straw is reduced to a pnlpy mass. The pulp is then removed from the boiler, and the liquor is 'witlnlmwn, to be used in the preparation of thenoxt batch of straw, as above described,

asufiieient quantityofslaked lime being first introduced into the liquorflnorder to'rcuder the soda, which hasbeeome neutral, again caustic.

the pulp also greatly improved, owing to the remdval by W ng of so much of ,theibreigflj matter.

Itis important that previous j'to the application to the prepared strawof the alkaline solution the latter should be heatedto the degree specified, as the time required for the op-' .eration is not only thus greatlyshortened,but

the full strength of the alkali is obtained to dissolve the gluten and silica, whereas if "the alkali were introduced cold nto the boiler,-a u d then heated, it would be toaconside ablo c:\*=

" tent diluted by the steam, and would not consequently be soeflicientinits action.

' In the ordinary process it; has becn usual to introduce the straw, watery-and lycinto a boiler, and then heat the wholeuntil the gluten and silica aredissolved. By this'process, howv ever," the pulp obtained is inferior in quality, and a much greater amount of time is required to complete the operation, whilei the pro'poia tion of soda used is more than"twiceas great as is required by the above-described process.

I claim as my invention and desire to secure by LettersPatent- 1. Manufacturing paper-pulp from straivhyj a process substantially as described.

2. Subjecting the prepared straw to thejacg tion of a hot solution of alkali prior to boil forth; for

ing the same, substantially as s the purpose specified.

In testimony whereof I have signed my name to this specification in the presence of two sun scribing witnesses. y 1 r THEODORE A; .NIXON. Witnesses: I.

CH-AREES E. Fosrun Jon: Wurre. r 

